First Online: 11 June 2015Received: 06 November 2014Accepted: 18 May 2015

Abstract

BackgroundGadolinium Gd Extracellular volume fraction ECV by Cardiovascular Magnetic Resonance CMR has been proposed as a non-invasive method for assessment of diffuse myocardial fibrosis. Yet only few studies used 3 T CMR to measure ECV, and the accuracy of ECV measurements at 3 T has not been established. Therefore the aims of the present study were to validate measurement of ECV by MOLLI T1 mapping by 3 T CMR against fibrosis measured by histopathology. We also evaluated the recently proposed hypothesis that native-T1 mapping without contrast injection would be sufficient to detect fibrosis.

Methods31 patients age = 58 ± 17 years, 77 % men with either severe aortic stenosis n = 12 severe aortic regurgitation n = 9 or severe mitral regurgitation n = 10, all free of coronary artery disease, underwent 3 T-CMR with late gadolinium enhancement LGE and pre- and post-contrast MOLLI T1 mapping and ECV computation, prior to valve surgery. LV biopsies were performed at the time of surgery, a median 13 1–30 days later, and stained with picrosirius red. Pre-, and post-contrast T1 values, ECV, and amount of LGE were compared against magnitude of fibrosis by histopathology by Pearson correlation coefficients.